This website makes available spatial and temporal data for commercial marine emissions inventories for cargo traffic in shipping lanes serving North American coastlines. A set of geographically resolved inventories were produced that describe air emissions for a 2002 baseline year. Annual gridded inventories are provided for the following pollutants: Sulfur (SOx as SO2), Nitrogen (NOx), Carbon dioxide (CO2), Particulate Matter (PM), Hydrocarbons (HC), and Carbon monoxide (CO). Monthly gridded inventories for each pollutant.

Units are kg per 4 km x 4 km (16 sq km).

Ship Traffic, Energy, and Environmental Model Output for North America. Illustration of domain extent and emissions per 16 sq km grid for SO2.

With partial funding from the the California Air Resources Board (ARB), and the Commission for Environmental Cooperation of North America (CEC), this inventory of commercial marine emissions for North America supports ARB, CEC, western regional states, United States federal, and multinational efforts to quantify and evaluate potential air pollution impacts from shipping in U.S, Canadian, and Mexican coastal waters.

The inventory was estimated spatially using the Waterway Network Ship Traffic, Energy and Environment Model (STEEM) characterizes ship traffic, estimates energy use, and assesses the environmental impacts of shipping. STEEM uses an empirical waterway network based on shipping routes revealed from observed historical ship locations. The ship traffic module of STEEM geographically and temporally describes ship traffic based on an empirical waterway network, historical ship movement data, and ship attributes data. Applications of STEEM include producing spatially-resolved energy and emissions inventories, assessing the impacts of shipping activities on the environment, e.g. invasive species carried by ballast water, interaction between ships and marine mammals, evaluating navigation safety, and other potential uses, e.g. logistics planning and disaster response planning. Research on applying STEEM on estimating the probability of the interaction between ships and whales is underway. The application of STEEM on navigation safety evaluation and other uses is reserved for future research.

The ARB/CEC report describing the baseline inventory is available here in pdf format.

The ARB report describing 2010 and 2020 forecast scenarios is available here in pdf format.

Zip files containing forecasts for 2010 and 2020 in ASCII format are available.

Site Updated 22 April 2007

We produced pollutant inventories in both ASCII and ArcGIS raster formats. The raster files associated with aux files and index files, so we zipped the sets into annual and monthly folders for download: